Day-405 | Daily MCQs | UPSC Prelims | SCIENCE AND TECHNOLOGY

Answer: B
Explanation:
In the wake of the energy crisis fueled by the Russia-Ukraine war, the Geneva-based particle physics laboratory CERN, known for discovering the ‘god particle’ in 2012, has reduced its energy intake.
• The Large Hadron Collider was successfully reignited for the third time July 5, 2022 — 10 years after it enabled scientists to find the elusive ‘God particle’ or Higgs Boson. Since then, it has discovered three exotic particles, according to the European Organization for Nuclear Research (CERN).
• The Higgs Field and its particle component, the Higgs Boson, explain why some particles that seemingly ‘should not’ have mass do, and in a larger sense, why any particles have mass at all. This is why the Higgs Boson became known as “the God Particle.”
• In the last decade, scientists have learned how the ‘god particle’ dies or decays, according to CERN. The Higgs Boson has a short lifespan. Once it is created during the particle collisions, it sticks around for merely less than a trillionth of a billionth of a second or, more precisely, 1.6 x 10-22 seconds.
• The Higgs boson is the fundamental particle associated with the Higgs field, a field that gives mass to other fundamental particles such as electrons and quarks.
• Experiments in the last decade have also demonstrated that fundamental particles such as top quarks, bottom quarks obtain their mass from their interactions with the Higgs field.

Answer: C
Explanation:
The 1/4/6×24 (one, four, six by 2024) campaign calls for TB patients to have access to evidence-based, long-awaited, shorter, less toxic treatment. But without mass availability of drugs, can India afford to adopt the protocol, remains a big question. The new campaign aims for the use of a one-month regimen (Isoniazide + Rifapentin) for latent TB infection (LTBI), a four-month regimen (Moxifloxacin+Rifapentin+Isoniazide+Pyrazinamide) for drug sensitive TB (DSTB) and a six-month regimen (Bedaquiline+Pretomanid+Linezolid) for drug-resistant TB (DRTB).
• Pretomanid is the third new drug developed for TB in over half a century, after bedaquiline and delaminid. It is a novel compound developed by non-profit organisation TB Alliance that has a collaboration with Mylan to commercialise the drug.
• The new drug is part of a three-drug (bedaquiline, pretomanid and linezolid), six-month, all-oral regimen for the treatment of people with extensively drug-resistant TB (XDR-TB) or multidrug-resistant TB (MDR-TB) who are treatment-intolerant or non-responsive.
• However, concerns have emerged on registering pretomanid, the logistics of rolling out a three-drug combination, their individual safety features and its price in high-disease regions such as India.

Answer: C
Explanation:
• Photochemical smog is a type of smog produced when ultraviolet light from the Sun reacts with Oxides of Nitrogen in the atmosphere. It is visible as a brown haze, and is most prominent during the morning and afternoon, especially in densely populated and warm cities.
• Stages of formation of photochemical smog:

Answer: D
Explanation:
Context: Slapped with penalties by the pollution board as well as being told off by the National Green Tribunal (NGT) for not clearing the fly ash of thermal plants, the Haryana Power Generation Corporation Limited (HPGCL) has now decided to make money out of it.
• Fly Ash: Ash is produced whenever combustion of solid material takes place. Fly ash is one such residue which rises with the gasses into the atmosphere. Fly ash is a very fine powder and tends to travel far in the air. The ash which does not rise is termed as bottom ash.
• Composition
o Aluminium silicate (in large amounts)
o Silicon dioxide (SiO2) and
o Calcium oxide (CaO).
• Fly ash particles are oxide rich and consist of silica, alumina, oxides of iron, calcium, and magnesium and toxic heavy metals like lead, arsenic, cobalt, and copper.
• Environmental effects:
o If fly ash is not captured and disposed of properly, it can pollute air and water considerably.
o It causes respiratory problems.
o Fly ash in the air slowly settles on leaves and crops in fields in areas near to thermal power plants and lowers the plant yields.
• Advantages:
o Cement can be replaced by fly ash up to 35%, thus reducing the cost of construction, making roads, etc.
o Fly ash bricks are light in weight and offer high strength and durability.
o Fly ash is a better fill material for road embankments and in concrete roads.
o Fly ash can be used in reclamation of wastelands.
o Abandoned mines can be filled up with fly ash.
o Fly ash can increase the crop yield and it also enhances water holding capacity of the land.

Answer: C
Explanation:
In a former gold mine a mile underground, inside a titanium tank filled with a rare liquified gas, scientists have begun the search for what so far has been unfindable: dark matter. Scientists are pretty sure the invisible stuff makes up most of the universe’s mass and say we wouldn’t be here without it but they don’t know what it is.
The visible universe including Earth, the sun, other stars, and galaxies, is made of protons, neutrons, and electrons bundled together into atoms. They make up only 5% of the universe.
• Galaxies in our universe seem to be achieving an impossible feat. They are rotating with such speed that the gravity generated by their observable matter could not possibly hold them together; they should have torn themselves apart long ago. Scientists theorize that something we have yet to detect directly is giving these galaxies extra mass, generating the extra gravity they need to stay intact.
• This strange and unknown matter was called “dark matter” since it is not visible. Dark matter outweighs visible matter roughly six to one, making up about 27% of the universe.
• Dark energy makes up the remaining 68% of the universe and appears to be associated with the vacuum in space.It is distributed evenly throughout the universe, not only in space but also in time, in other words, its effect is not diluted as the universe expands.
• A neutron star is the collapsed core of a giant star. Neutron stars have a radius on the order of 10 kilometers and a mass of about 1.4 solar masses. Hence it has an enormous density. They result from the supernova explosion of massive stars.
• When the supernova results in a neutron star core, the electrons, and protons in the core are merged to become neutrons, so the newly born 20-km-diameter neutron star containing between 1.4 and 3 solar masses is like a giant atomic nucleus containing only neutrons.
• If the neutron star’s mass is then increased, neutrons become degenerate, breaking up into their constituent quarks, thus the star becomes a quark star; a further increase in mass results in a black hole. Hence black holes result from massive neutron stars. Neutron stars’ split does not result in black holes.